Inductance



April 14, 1925,

`o. MElRowsKY INDUCTANCE 4 Sheets-Sheet 1 Filed June l1, 1923 April 14,1925. 1,533,749

. O. MEIROWSKY INDUC'IANCE Filed June 11, 1923 4 Sheets-Sheet 2 @415- O8 l y I uuml llmll pr M, 1925. 119533,74

o MEIROWSKY v INDUGTAN'CE 'Filed June 11, 1925 4 sheets-sheet s|lllllllllllllll!llllulllllllllllll! April 14, 1925. 1,533,749

o. MElRowsKY INDUCTANCE Filed June `11, 1925 4 sheets-sheet 4 *W3 @my12,. @W15 @y 1lb,

LSU

Patented Apr'. 14, 1925..

Unirse STATES OSKAR MEIROWSKY, 0F PALISADE, NEW JERSEY.

INDUc'rANcn application med June 11, 192s. serial No. l'e4-1,691.

To @ZZ whom it may concern.'

Be it known that I, OSKAR MnmoWsKY, a citizen of the Republic ot'Germany, residing at Palisade, in the county of Bergen and Siate et' NewJersey, have invented a certain new and useful Improvement in anlnduciance, ot' which the following is a specilication. Y

My invention relates broadly to electrical apparatus, and moreparticularly to an inductance for connection in various electricalcircuits.

One of the objects of my invention is to provide an inductance device bywhich extremely accurate degrees of coupling and small increments otinductance may 4be obtained in electrical circuits.

Another object of the invention is to provide an inductance devicewherein a selected number of turns in either a primary or secondarycircuit maybe readily effectively placed in an electrical circuit, andwherein any fractional part of a turn may be secured.

A. further object of the 'invention is to provide a system ofinductively related coils wherein the turns of the 'primary alternatewith the turns of the secondary.

A still further object of the invention is to provide means whereby aselected number of turns of an inductance may be arranged in anelectrical circuitwith apredeterinined degree of coupling with aninductance connected in a diii'erent circuit.

My invention resides in various constructions by which the turns oi. theprimary winding ot my apparatus are alternately positioned between theturns of the Sec0ndary winding.

Other objects will be understood from the following specilication byreference to the accompanying drawings, in which:

Figure 1 is a cross-sectional view of one embodiment of the inductanceot my invention; Fig. 2 is a side elevation ofthe inductance illustratedin Figgl'; Fig. 8 is a plan view of the inductance shown in Fig. 1;Figs. 11 and 5 are views partially in section taken along lines 11-4 ofFig. 1 and 5-.- of Fig. 3; Figs. G and 7 are wiring diagramsillustrating applications of my invention; Fig. 8 is a View partially incross section oi a modified form of my inductance having a plurality ot'layers in the primary and secondary windings; Fig.

9 is a cross-sectional view of a modified form of my inductance; Fig. 10is a view partially in section taken on line 10-10 of Fig. 9; Fig. 11 isan end'view in modified form ofiinductance illustrated in Fig. 9; Figs.12, 13 and 14 are views of another modification in inductance of myinvention showing the alternate positions of primary and secondarywindings; and Figs. 15, 16, 17, and 18 show further forms in which myinvention may be embodied.

In the drawings, the apparatus is mounted upon a bate 1 with standards 2and 3 atl opposite ends thereof forming bearings for shaft members 5 and12. The shaft member 12 is secured in the standard 3 and has a hollowbore which receives and supports the shaft 5. The shaft 5 comprisesinsulating material reduced in cross sec-tion at 9 to receive a metallicsleeve 13 forming a. contact bearing and a keyway along which the member7 is adapted to slide. The member 7 carries the turns 8 of a secondaryinductance which are alternately positioned between the turns 10 of arimary inductance. The member 12 is threaded as represented at 14 withthe same pitch as exists between the turns of the secondary coil 8. Athreaded carrier 15 is secured to the other end of the secondary coil 8,the end of the secondary passing through insulated bushing 29 (Fig. 4)positioned in metallic tube 18. The carrier 15 is seemed in one end ofthe tube 18 by means of the insulated disk 16. Upon rotation of theshaft 5 by means of hand knob 6 the entire secondary 8 between member 7and carrier 1.5 advances to such positions as represented by dottedlines 7 and 8', the member 7 sliding along the keyway in sleeve 13throughout the portion of the shaft 5 at 9. The primary inductance 10with its turns positioned alternately with those of the secondary issolidly supported at 22 and 81. A. sliding contact 19 is carried by thetubular memberk 18 making contact with the turns 1() of the primary. Atthe opposite end of the tube 18 av Contact 20 is provided supportedYupon bracket 21 whereby electrical connection is completed through themetallic walls of the Cylinder 18 with the sliding contact -19independent of the position of the cylinder in processl of advancing tosuch position as 18. The. primary turns are tapped as indicated at 25and connections taken to switch points fii'i mounted upon panel l. rEheterminals tor the primary inductance are represented at and 3?. theterminal 32 beingr connected to the switch arm 31 selecting the desirednumber ol turns in the primary circuit- The, terminal 33 is connect-edto the lastturn of the primary at Sl. rlhe contact Q which makesconnection with the metallic cylinder 18 is connected through conductor9A with switch Contact 82 so that when the switch arm 3l is positionedover contact S2 any fractional part of a turn in the primary inductanceis connected in the circuit between terminals 3Q and 83. The terminalsvtor the secondary inductance are represented at 82% and 8l. |lierminalSi connects to a switch fill haring contacts 35 and 3G. Contact 236 isconnected through a conductor 28 with a wipingn Contact 27 bearing,`upon collector ring 2G in electrical connection with sleere l and fromthence to the end ot secondaryY coil S through member i'. rl`he otherend ot the secondary coil 8 being permanently anchored in member at alltime@ in electric-al connection with terminal Si) as the member 15advances along the threads ll in member 12. The contact is connected toan adjustable contact l1 mounted upon a bracket 37 secured to panel.l'he contact el may be longitudinally moved by knob l. under 'tensionof spring' 39 proicctincY through a slot in the panel Noti-hes lll areprovided-spaced in accordance with the pitch ot the secondary turns 8.ly provriding` this adjustable contact 41 a 'particular number of turnsin the secondary may be subjected to the inductive effect ol a exactlyequal number of turns or any ininute fractional part ot a turn of theprimary. is the knob G is rotated the Secondary coil 8 with the primarysliding contact assembly 19, 18, 1G and l5 rotates and advances axiallyto the right. it all times during' rotation and while at rest the turns8 ot the secondary contact with adjustahlr` contact ll and from therethrough switch con tact 35 and switch 34 with terminal post Si. 'thatportion of the secondary advancing,Y beyond ll when the switch 3l is poiitioned upon contact 35 is dead or not in uv rThe primary contact 19advances to the saine eti'- tent and the turns ot the primary 1li. allot the turns to the lett ot contact' 19 are dead.

in intinite variety ot adjustments may 4be obtained by use of myinductance as represented by the following examples. fr diminishingnun'ibcr ot turns of the sicondary may be obtained while current isflowing; in a given number oE turns ot the primar)I lO, Switch S isplaced on contact 232i. The primary switch 3l is placed on contact'SEUR. The lull number oii 'turns in the primary will now be always inthe circuit` irre maar@ spective oi the -sition of Contact l). By movingthe primary switch 31 over the contacts with the exception ol contact 82Cuts out the primary by a t'ull number of turns. By moriirg` switch 31to Contact 82 a full number of turns and a fractional part of a turn maybe included in the primary.

Another combination which may be obtained provides the inll number ofturns in the secondary and a. particular number of turns in the primary.rlo accomplish this switch is moved to contact 3G placing thc entiresecondary in the circuit. and the switch arm 3l is placed on aparticular contact conn cling in a certain number of turns ofv theprimary.

Another combination provides a i'ull number oil turns in the secondaryand a diminishing number oi turns in the primary where switch lcrer 31on contact Sti and where switch arm 3l moved over the range of contactste "ct a desired number ot turns.

further combination may be obtained with diminishing secondary turns butwith more turns in the circuit than are interspaccd with the primaryturns. 'this is accomplished by placing switch arm 3l on contact S5 andmoving; the slidingY contact ll to the right on rac-lr #10, the notchesin which are spaced similarly to the pitch ot the screw threads il. lymoving contact Lll one, two, three cr more spaces the secondary turns 8do not make contact with contacty l1 immediately upon emerging l'rom theprimary 'turns 1U, but one, two7 three or more spaces reinored from thelast turn el the primary. Each space is equivalent to one turn so Vthatthere are always one, two, three or more turns,` as the case may be7 incircuit than are intcrmeshed with the primary turns. Simultaneously withthis operation the primary turns may be selected by inoringr switch arm3l.

My iuductance is applicable for extremely tine tuning in electricalcircuits, particularly circuits in radio apparatus wherothe electricalconstants must be adjusted to resonance with the incomingr treipiencics.YWith my inductance the electrical envelop characA terist'ic or" thereceiving circuit may be made to exactly coincide with the envelopchar-ai teristic ot' the incoming signal energy. This is or great'in'iporta-iuce where precise tuning' oi' circuits is necessary toreceive signals` transmitted on closeiy adjacent wa velengthf-:, ortoliz; the precise wavelength o le the transinitier.

Figs. t? and indicate applications ol" my variable inducfance. ln Fig.(3 the .si-roi ary S and primary l() loi-in the. roupli means between areceivingr antenna system and a receiving apparatus. wiil be noted 'thatthe primary lt) and secondal,Y 8 are shown with their conductorsalternately positioned. A condenser 44 is used fer tuning the secondarycircuit. Electron tubes 45 serve as radio frequency amplifiers, tube 46functions as a detector, and tubes 47 operate as audio frequencyamplifiers. In Fig. 7 my inductance is shown as auxiliary to avariocoupler having Awindings 48 and 49. Fine tuning is obtained by theinnite variety of' adjustments `capable in my -inductance while broadtuning is obtained by the usual coupling system.

It may be desirable to utilize a multiple layer coil for the primary andsecondary windings as represented in Fig. 8 wherein the four layers ofsecondary -coil 8 are axially moved relative to the four layers ofprimary coil 10.

ln the modified form of inductance illustnated in Fig. 9 an insulatedtube 53 is provided supported at each end in standards 56 and 57 onbase 1. The secondary coil 8 is alternately wound between the turns ofthe primary coil 10 in grooves separated by the insulated threads 55.The primary 10 is stationary and is tapped at various turns as indicatedat 61, which taps are brought to switch points 60 on panel 58 wherebyswitch 59 may select a desired number of turns in the primary, thesecondary coil 8 is attached to hand wheel 54, the ends thereof beinganchored to collector rings 61 and 62. The hand Wheel 54 rotates inthreads upon the cylinder 53 advancing the secondary relative to theprimary very gradually.4 Sliding contacts 63 and 64 are c-arried upon arunner 65 arranged to slide on guide rods 66 as the hand wheel 54advances. Flexible conductors67 connect to contacts 63 and 64 withbinding posts 68 forming the terminals for the secondary.

In Fig. 12 the secondary 8 and primary 10 are alternately wound in avertical plane. rlhe coupling may be changed by rotating the hand wheell6 serving to rotate the coil 8 in dotted line positions 8 as indicatedin Fig. 13.

Fig. 13 taken on line 13--13 of Fig. 12 indicates the primary 10supported in stationary position through the stationary shaft 69.

Fig. 14 illustrates a further modification where the shaft 70 isadjacentthe base 1 and supports the stationary primary coil 10 betweenthe turns of which the secondary coil 8 may be moved.

Figs. 15 and 16 illustrate a further modification in which the primarycoil 10 and secondary coil 8 are spirally wound, one winding alternatingwith the other winding. rlhe primary Winding 10 is supported on panel 71and the secondary winding 8 on panel 72. swing relative to panel 7l andmay assume position 72 with the secondary coil at 8 for changing thecoupling lbetween the cir- 'lhis panel '72 is pivoted to cuits. rlhedistance between the coils 8 and l() may be changed by loosening handscrew 74 and laterally moving the panel 72 along guides 73. ln this waythe spiral windings may be intermcshed in a common plane when in theposition of maximum inductive effect. This form `of inductance mightutilize a standard 77 with advancing screw 76 operating from hand wheel78 moving panel 74 carrying secondary 8 so that it may be intermeshedwith the spiral 10.

Figs. 17 and 18 illustrate another modification of my invention whereinthe secondary 8 and primary 1() are wound in the form of helixes. Theprimary helix 10 is supported rigidly on the base 1 while the secondaryhelix 8 is carried by shaft 7 S) which may be rotated 'by hand wheel 80to vary the coupling between the circuits.

lhile I have described my invention in certain specific embodiments, theillustrations of the primary and secondary windings have necessarilyshown the turns of relatively large diameters in order to clearly bringout the invention, but it is understood that various sizes of coils maybe employed and that the apparatus is applicable in any electricalcircuit and that no limitations upon the invention are intended otherthan are imposed by the Scope of the appended claims.

`What I claim and desire to secure by Letters Patent of the UnitedStates is as follows:

1. An inductance system comprising in combination a primary coil and asecondary coil, said primary coil being fixed in position with its turnsspaced one from another, and means for moving the turns of saidsecondary coil in an axial direction between the turns of said othercoil.

2.'An inductance system comprising in combination a spiral primary coiland a spiral secondary coil, said primary coil being fixed in posit-ionwith its turns spaced apart, said secondary coil having its turns spacedapart and alternately positionedbetween the turns of said primary coil,and means for varying the coupling by relatively moving one of saidcoils in an axial direction whereby one winding intermeshes with theother winding.

3. An inductance system comprising in combination a straight helicalprimary winding having itsturns spaced apart and fixed in position, astraight helical secondary winding having its turns similarlyy spacedapart, and means for variably intermeshing the turns of said secondarywindingv with the turns of said primary winding.

4. An inductance system comprising in combination a helical primarywinding having its turns spaced apart, a helical secondary windinghaving its turns similarly spaced apart, of said turns havingsubstantially the same diameter in corresponding layers thereof and mfais for a "ally moving said secondary vvi.. M. g relative to said primarywinding' for the purpose of having more or less turns of said windingsmutually intei'mesh to varying degrees.

5. An inductance system comprising in combination helical primary andsecondary windings having their turns mutually internieshed, means forvarying; the coupling between said windings axially moving one of saidwindings relative to the other, a switch for selecting the effectivenumber of turns in one of said windings7 a contact rotatablesimultaneously with the axial movement of the other of said. windingsiter selecting any fractional part of a turn in said winding, and anadjustable contact for varying the eective number ot turns in saidaxially movable winding.

6. An inductance system comprising in combination helical primary andsecondary windings having their turns mutually inter- Ineshed, a shaftaxially positioned within said windings, and a pair ot carrierslongitudinally movable on said shaft, one oi" said carriers arranged toadvance one of said windings relative to the other.A and, the otheradapted to inalze variable turns of said other windot said carrieContact vvitl; the ing.

i inductance system comprising` in combination helical primary andsecondary windings having their turns mutually interineshed7 aninsulated slia'': positioned through said ivindings7 a bearing memberfor one end oi said shalt1 slotted metallic sleeve carried 1oy anotherportion oi" said shaft, a carrier longitudinally movable along saidslotted sleeve, threads on said bearing member.l and a second carrierrotatably mounted on said threads. said carriers forming supportingmeans for said secondary winding whereby said secondary may be axiallymovable relative to said winding.

8. An inductance system, comprising in combination a primary winding anda secondary winding:J the turns of one winding being mounted torrotative and axial movement with respect to the turns of the otherwinding whereby the turns of one *inding' may be alternately positionedbe weon the turns of the other winding i'or securing maximum inductiveeect between the windings.

